QuickShip Electronics via eBay offers the Pioneer Mini Stereo System for $99.99. Apply coupon code "PBACK2SCHOOL20" and check out with PayPal to drop the price to $79.99. With free shipping, that's tied with last month's mention as the lowest price we've seen. (It's the best deal we could find now by $30.) It features two speakers, a CD player, AM/FM radio, Bluetooth 4.1 with NFC pairing, and USB. Deal ends July 16.

Note: This coupon can be used twice per account.